Band offsets in ITO/Ga₂O₃ heterostructures

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>The valence band offsets in rf-sputtered Indium Tin Oxide (ITO)/single crystal β-Ga<SUB>2</SUB>O<SUB>3</SUB> (ITO/Ga<SUB>2</SUB>O<SUB>3</SUB>) heterostructures were measured with X-Ray Photoelectron Spectroscopy using the Kraut method. The bandgaps of the component materials in the heterostructure were determined by Reflection Electron Energy Loss Spectroscopy as 4.6eV for Ga<SUB>2</SUB>O<SUB>3</SUB> and 3.5eV for ITO. The valence band offset was determined to be −0.78±0.30eV, while the conduction band offset was determined to be −0.32±0.13eV. The ITO/Ga<SUB>2</SUB>O<SUB>3</SUB> system has a nested gap (type I) alignment. The use of a thin layer of ITO between a metal and the Ga<SUB>2</SUB>O<SUB>3</SUB> is an attractive approach for reducing contact resistance on Ga<SUB>2</SUB>O<SUB>3</SUB>-based power electronic devices and solar-blind photodetectors.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We measured the band offsets of ITO on Ga<SUB>2</SUB>O<SUB>3</SUB>, a promising wide bandgap semiconductor for solar-blind detectors and power electronics. </LI> <LI> The band alignment is nested (type I), with a valence band offset of −0.78eV </LI> <LI> The results show the use of ITO interlayers will be beneficial to improving Ohmic contacts on Ga<SUB>2</SUB>O<SUB>3</SUB>. </LI> </UL> </P>